BYU student builds car that gets 1,331 miles per gallon

This is an archived article that was published on sltrib.com in 2013, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

Provo, Utah • To get better gas mileage from a car, you generally have to make some sacrifices, such as plush comfort or quick acceleration. And if you make enough of those sacrifices, your miles per gallon can skyrocket.

A team of BYU students built such a vehicle, and got the most miles per gallon of any university team in the country in a recent competition  1,331 mpg to be exact. That's right, there is no decimal point in that figure.

"Our car got the highest gas mileage so we feel like winners," Gary Ellingson, one of the student designers, said.

The car is not meant to drive in regular traffic. It stands about 25 inches off the ground at its top, is about nine feet long and about 30 inches wide. It weighs about 100 pounds.

Seven mechanical engineering students designed and built the car, with their adviser, Jerry Bowman. Caroline Sorensen, a student from Boston, was chosen to drive the car, as she weighed the least of the team members. The rules of the contest, which took place earlier in June in Marshall, Mich., state that the driver must weigh 130 pounds; if he or she weighs less, the difference must be made up with weights. This is similar to jockeys in a horse race which must meet specific weight requirements.

Sorensen reclines on her back while driving and looks out over her toes to see where she is going. The first of the two-day competition finds the teams working to qualify for the actual event. They are judged whether they meet the specifications and whether or not they are safe.

BYU's car, for instance, has three separate switches which must all be turned on in order for the car to operate. That eliminates the chance start if someone is working on the vehicle and happens to hit one of the switches.

Twenty-five teams from across the country registered for the event; 19 passed the tech review and were allowed to participate in the final day's "race."

The BYU vehicle took second overall, but captured first for the miles per gallon portion of the contest. Penn State came in second with 40 mpg less.

Each vehicle was tested for its maneuverability, going through a series of cones in a slalom-like course. The big event, however, was the fuel efficiency, in which they drove six times around a 1.6 mile track.

"It is super cool to drive it," she said. "You are learning a lot of stuff as you go. It is a really awesome project."

Driving such a vehicle takes planning and patience. The rules indicate they must average 15 mph, but they sometimes go as slowly as 2 mph. The process is called burn and coast. Sorensen turns on the engine, which is a modified lawn mower or rototiller engine, gets the vehicle up to perhaps 25 mph, then cuts the engine and coasts.

On the sidelines, the pit crew is furiously making calculations about the speed. The vehicles have 36 minutes and 22 seconds to complete the course and get penalized if they go over that time. As they make the calculations, they tell her by walkie talkie if she can slow down or speed up.

She can also tell by the way the car performs.

"The decision when to cut the engine is by feel," she said. "I listen to the engine. You could probably tell the speed by the frequency."

A regular vehicle uses extra fuel to restart an engine, but the competition vehicle has been modified to lessen that effect.

"Our engine is a lot more efficient startup than a regular car," Ellison said. "You do a lot of tradeoffs."

With the close quarters and lots of windows in the car, it can get rather uncomfortable. Sorensen said she does not suffer from claustrophobia, but was still affected by the heat. Prior to the event, most of the testing was done in the spring, and the competition itself was at lower temperatures than Utah has been experiencing lately.

"It is 15 degrees hotter (in the car) than outside," she said. "It feels more like 20."

Nevertheless, she is excited by the opportunity.

Two semesters of planning, design and building went into the vehicle before the competition.

Ellingson, a team member from Mesa, Ariz., said this is the second year BYU has had a vehicle in this competition, and they refined the entry from last year.

"We took last year's car and improved it," he said. "We actually rebuilt or modified most of it."

That included a new body, engine and steering. The shell is made of carbon fiber with some aluminum components.

Some of the main goals are to reduce the weight of the vehicle and increase its aerodynamic properties.

Despite working on it for a school year, even while they were on their way to the event, they were already thinking of other modifications to be made in the future.

"We thought it would be good to try to improve the bearings and use different tires," Bowman said. He said one of their next goals is to get the vehicle's weight down even more.

Two of the team members are already employed by Ford Motors. Some of the others are planning on going on to graduate school. Sorensen plans on attending MIT and is considering working in its automotive lab.

"We have learned a lot from this project," Sorenson said. "It has been really fun. We have taken the stuff we have learned and applied it and seen it come together. One of my favorite things has been watching all the pieces come together."

Reader comments on sltrib.com are the opinions of the writer, not The Salt Lake Tribune. We will delete comments containing obscenities, personal attacks and inappropriate or offensive remarks. Flagrant or repeat violators will be banned. If you see an objectionable comment, please alert us by clicking the arrow on the upper right side of the comment and selecting "Flag comment as inappropriate". If you've recently registered with Disqus or aren't seeing your comments immediately, you may need to verify your email address. To do so, visit disqus.com/account. See more about comments here.